If a landlord refuses to rent an apartment to two single women living together, this is discrimination based on which federally protected class?

Discrimination against two single women living together falls under the classification of sex discrimination. The Fair Housing Act prohibits discrimination on the basis of sex, which includes treating individuals differently in housing situations due to their gender. In this case, the landlord's refusal to rent to two women specifically highlights a bias based on their sex, as equal treatment would entail allowing individuals of any gender to live together without prejudice.

This scenario showcases how sex can be a determining factor in housing decisions, demonstrating a violation of their rights under fair housing laws. The other classes listed, such as race, religion, and national origin, while also protected categories under the Fair Housing Act, do not apply to the situation of the landlord's refusal based solely on the tenants being women.